Banning mobile phones from schools has the effect of giving pupils an extra week's education over the course of an academic year, researchers say.
The study, published by the London School of Economics, looked at schools in four English cities and found test scores increased by more than 6% in those which banned phones.
Low-achieving and low-income students improved the most, researchers claim.
More than 90% of British teenagers own a mobile phone.
Report authors Louis-Philippe Beland and Richard Murphy say despite the benefits of new mobile technology phones cause distractions, reduce productivity and are detrimental to learning.
"We found that not only did student achievement improve, but also that low-achieving and low income students gained the most," the economists said.
"We found the impact of banning phones for these students was equivalent to an additional hour a week in school, or to increasing the school year by five days."
The report surveyed the test scores of secondary schools in Birmingham, Leicester, London and Manchester before and after phone bans were introduced.
Since April 2007, teachers have had the legal right to confiscate items from pupils but there is no UK government policy about mobile phone use in England with individual schools making their own policy.
In March, New York mayor Bill De Blasio lifted a 10-year ban on phones on school premises saying it would reduce inequality.
But the report authors disagree.
"The results suggest that low achieving students are more likely to be distracted by the presence of mobile phones while high achievers can focus in the classroom regardless of the mobile phone policy," the study says.
"Schools could significantly reduce the education gap by prohibiting mobile phone use, and so by allowing phones, New York may unintentionally increase the inequalities of outcomes."